On April 7, Prince Philip will be hosting a dinner at Windsor Castle organised by the Jewish National Fund. They will be marking the 60th anniversary of the establishment of the Israeli state. However this is not a private dinner. Nor is the JNF an ordinary organisation.

The JNF was established in 1901 as the land settlement wing of the World Zionist Organisation. It became one of the primary instruments involved in planning for the dispossession and expulsion of the Palestinians. Up until 1948 it purchased land for settlement, often from absentee landlords, and then evicted the peasants from that land. Unlike the normal practice under colonial rule, the Palestinians were not re-employed as wage labourers but excluded from the land altogether. This was the concept of Jewish land. But even by 1947 less than 7% of the land of Palestine had been bought up.

The JNF played a crucial role in planning for the ethnic cleansing of Palestine. In the years leading up to the establishment of the state of Israel, the JNF was a key voice in establishing a consensus in the Zionist leadership for "transfer". Although not discussed openly, among the Zionist leaders it was accepted that a Jewish state could only come into being if the Arabs were transferred out of the state. Palestine was a land where barely one-third of the inhabitants were Jewish, and even in the area allotted by the United Nations to a Jewish state, barely half of the inhabitants were Jewish. As the head of its Land Settlement Department, Joseff Weitz, wrote in his diary in 1940:

The only solution is to transfer the Arabs from here to neighbouring countries. Not a single village or a single tribe must be let off. [Ilan Pappe: The Ethnic Cleansing of Palestine, page 62]

Weitz later formed, with the authority of David Ben Gurion, a Transfer Committee. And between 1947 and 1949 an opportunity arose to put these ideas into practice. As Tom Segev recalled in Ha'aretz, a meeting was held in Haifa on March 27, 1948, concerning the fate of the Bedouin of Arab al-Ghawarina in the Haifa area. "They must be removed from there, so that they, too, will not add to our troubles," Yosef Weitz, of the Keren Kayemeth (Jewish National Fund), wrote in his personal diary.

The JNF occupies a unique position in Israel. It is nominally an independent organisation but in reality it is a contracted-out section of the state, controlled by unelected and unaccountable bureaucrats, carrying out functions that the state itself cannot be seen to do openly. The JNF functions as an ideological outpost of the Greater Israel movement and when the Israeli army razed to the ground the Palestinian villages of the Imwas, Yalu and Beit Nuba villages in 1967 and expelled their inhabitants, the JNF took over the construction of the Canada National Park on the ruins.

The JNF's position was formalised by the 1953 KKL Law whereby its memorandum of association had to be approved by the minister of justice. In November 1961 a covenant was signed between the state of Israel and the JNF which accorded the latter effective control of the land allocation policies of the state of Israel, which together with the Israeli Lands Administration, controlled 93% of Israeli land. According to Article 3a of its constitution, the JNF was established "for the purpose of settling Jews on such lands and properties" as it could obtain.

The British royal family have a constitutional role greater than their private prejudices. They are seen as the representatives of British society and their invitation to the JNF will inevitably be seen as giving a royal seal of approval to the Nakba, the Palestinian catastrophe. Britain's role in arming the Zionist militias who fell like wolves on largely defenceless villagers, while suppressing the 1936 Palestinian national uprising, is infamous enough without the monarchy celebrating the consequences of Britain's perfidy.

Not that the association between royalty and the most barbaric aspects of colonialism is anything new. Today's royals may hold gala dinners in celebration of the abolition of the slave trade and Wilberforce, but when slavery was a going concern, its most ardent supporters were royalty. Elizabeth I went into business as a partner of slave trader John Hawkins, Charles II was a major shareholder in the Royal African Company and William IV, then Duke of Clarence, spoke out strongly against the abolition of the slave trade and emancipation in the House of Lords.

With the solitary exception of Princess Diana and her campaign against landmines, the royals have been associated with the most atavistic and bloody aspects of British imperial rule. From the Indian Mutiny and the Amritsar massacre to the Hola death camp in Kenya, the royals have always been associated with militarism and empire. Prince Harry's role in Afghanistan is a continuation of this inglorious history.

In 1995 an Arab couple, the Kadans, tried to buy an apartment in Katzir. For 10 years the JNF and the Israeli Lands Authority tried to prevent the leasing of "Jewish" land to non-Jews. Eventually the supreme court ruled that state land could not be sold to Jews only.

This caused huge embarrassment among Jews worldwide. How could Jews protest against anti-Semitism when condoning blatantly racist practices in Israel? America's Reform movement, to which most Jews adhere, condemned the practice unequivocally.

The JNF itself, though, was anything but embarrassed. It began a campaign to reverse the court's decision and last summer a JNF Bill was introduced into the Knesset, where it was passed on the first reading by 64-16 votes. Under the headline "KKL-JNF - Trustee for the Jewish People on its Land" it noted that:

A survey commissioned by KKL-JNF reveals that over 70% of the Jewish population in Israel opposes allocating KKL-JNF land to non-Jews, while over 80% prefer the definition of Israel as a Jewish state, rather than as the state of all its citizens.

The implications are quite clear. If Israel is a Jewish state then it cannot be a state of its own citizens, still less a democratic state.

This prompted Israel's liberal newspaper, Ha'aretz, to publish an outspoken editorial, "A racist Jewish state", in which it wrote:

"Every day the Knesset has the option of passing laws that will advance Israel as a democratic Jewish state or turn it into a racist Jewish state. There is a very thin line between the two. This week, the line was crossed."

Even the staid old Jewish Chronicle ran a debate: "Is it racist to set aside Israeli land for Jews only?"

Yet this is part of a wider debate about the "demographic problem", which is shorthand for there being too many Arabs. Academics such as Professor Arnon Sofer, of Haifa University, are quite blatant about this "problem":

"You should remember that on the same day as the Israel Defense Forces is investing efforts and succeeding in eliminating one terrorist or another, on that very same day, as on every day of the year, within the territories of western Israel, about 400 children are being born, some of whom will become new suicide terrorists."

The JNF sits on the opposite side of the fence from those who wish to see Israel as a state of all its citizens as opposed to just its Jewish ones. It is bad enough that our prime minister, Gordon Brown, is a patron of the JNF. But for the royal family to have as their guests those who are dedicated to maintaining Israel as a state of only a part of its citizens is a disgrace.

A letter from Brigadier Sir Miles Hunt Davies, private secretary to the Duke of Edinburgh, seeks to excuse the royal hosting of the JNF by stating that "the proceeds from the dinner are going to a number of charities, one of which will be the Israeli Youth Award for Young People, which is the Israeli branch of the Duke of Edinburgh's Award. This charity plays a significant part in attempting to bridge the gap between young people of all faiths and backgrounds, in amongst other places, Israel and Jordan."

So, according to this logic, the royal family will be hosting a dinner for an organisation which explicitly discriminates against Palestinians and non-Jews because the proceeds will be going to a charity which apparently does the complete opposite. You couldn't make it up.